word problem

Question

Loudon County Phone Company charges a $100 activation fee plus a monthly fee of $0.05 per minute for every minute over 200 minutes each month. (So, there is no monthly charge for 0 – 200 minutes of use per month). show all work.

 

(a) Write an equation that can be used to determine a new subscriber’s first month’s phone bill, B(x), given the amount of minutes called, x. (Assume that the subscriber will make over 200 minutes of calls) '

(b) Determine the subscriber’s first month’s bill if the total minutes used was 650. Show work.

(c) Determine the number of minutes used if the new subscriber’s first month bill was $114. Show work.

Answer 1

a) B(x)=$100+(x-200)($0.05)

 

b) B(x)=$100+(650-200)($0.05)

    B(x)=$100+(450)($0.05)

    B(x)=$100+$22.50

    B(x)=$122.50

 

c) $114=$100+(x-200)($0.05)

    $114-$100=(x-200)($0.05)

               $14=(x-200)($0.05)

               $14=$0.05x-$10

               $14+$10=$0.05x

               $24=$0.05x

               $2400=$5x  (multiply both sides by 100)

               $2400/$5=x

               480=x (480 minutes used)

    check:  480-200=280 minutes @ $0.05 per minute equals 280*$0.05=$14 Plus $100 fee equals $114

Answer 2

Deleted duplicate answer